In the refrigerators with forced air circulation, the evaporator is positioned inside an air cooling compartment generally provided in the rear upper region of the refrigerator cabinet and presenting at least one circulated air inlet, which receives the air coming from the storing compartments of the refrigerator, and a refrigerated air outlet directed to said storing compartments.
In the combined refrigerators, the air cooling compartment is generally positioned behind the freezing compartment and in communication with the latter and with the refrigerating compartment through said refrigerated air outlet of the air cooling compartment, which outlet is opened to an adequate system of refrigerated air directing ducts.
In order to provide the necessary forced air circulation through the evaporator mounted in the air cooling compartment, drawing the air that is forced to circulate through the freezing and the refrigerating compartments, and returning the air to said freezing and refrigerating compartments after it has been refrigerated by the evaporator, the refrigerator is provided with a fan of axial flow, whose shaft is generally horizontally disposed and which is mounted to a divisional wall of the air cooling compartment through the air outlet of the latter defined by an opening in said divisional wall of the air cooling compartment.
In some prior art assemblies, the fan, comprising an electric motor to whose shaft is mounted a propeller, has said motor affixed directly to the wall of the air cooling compartment by means of a rigid support, which can take different forms, such as for example a tubular shell affixed to said divisional wall, coaxially to the outlet opening of the air cooling compartment.
Since the transmission of vibration from the electric motor to the remaining parts of the cabinet is one of the major sources of noise, it is known from the art the provision of mufflers or pads made of elastomeric material between the electric motor and the rigid support. This prior art constructive solution allows utilizing motors of low cost in which the tubular shell is replaced by a structural support with the approximate form of a cage. However, this constructive arrangement presents some disadvantages, such as the obstruction of part of the air intake area of the fan and the difficult fixation and replacement of the motor, requiring the disassembly of several other components (propeller, ducts, mufflers, etc).
Another known prior art solution uses a system in which the fixation is also made directly to the electric motor, but through a flexible annular support of elastomeric material, surrounding the body of the electric motor and incorporating substantially radial rods, whose ends are affixed to said divisional wall of the cabinet structure on which is provided the outlet opening of the air cooling compartment.
This construction of an elastomeric annular support with radial rods uses a small amount of material, incorporating the support and the mufflers in a single piece and allowing for the easy and rapid assembly and disassembly operations. However, this prior art solution is not sufficiently resistant to transportation, allowing damages to occur to the fan. The fact that the motor is directly affixed to the cabinet structure, having no cowlings for directing or conducting the airflow, results in efficiency loss of the forced air circulation system.
Besides the disadvantages mentioned above, the constructive solutions in which the motor is directly affixed to the cabinet by means of a rigid or flexible support make difficult or even infeasible to use fans provided from different suppliers, each fan requiring a respective adaptation for the motor support.